Electrical swivel connection



March 2s; 195o T. H. FAILE 2,502,252

ELECTRICAL SWIVEL CONNECTION Filed June 50J 1945 y i 156 /Z 55 O 13 Z 151, 30 y j ,o fa' n 15b 66 Afro/MEX 2 sheets-sheet 1v Marh Z8, 1950 v- T, H, FAILE 2,5(.)2,25'92 ELECTRICAL swIvEL CONNECTION Filed June so, `1945' 2 sheets-sheet 2 l f l.

IN V EN TOR. V

MEME/@ A fr0/WEE j C BY Patented Mar. 28, 1950 UNITED STATES PATENT OFFICE ELECTRICAL SWIVEL` CONNECTION Thomas H. Faile'vvhite Plains, Ni Y.

Application J une 30, 1945, Serial No. 602,505'

a' anims.

This invention relates to electrical swivel conl 'n'ections In spite of` the many types of` electrical swivel connectionsv which have previously been proposed 'for use, most users stillv employ extension cords in which the insulated leads must themselves take yup all the twists to which they are subjected. These leadsmoreover exert resistance :upon an appliance such as an electric iron, for

example, whenever the appliance is turned or .i

twisted. While the desirabilityof remedying these difculties has been apparent for many years, the practical art is still, so far as is known, 'awaiting the provision of a form of electrical -connection which meets the exacting electrical requirements and the precise mechanical requirements for satisfactory use and whichat the same time meets the practical requirements for ease of 'assembly and for repair.

Itv is accordingly an object. of theY invention toi:4 .1

Traction.

yAnother object is the provision of improved methods for assembling electrical swivel connections.

@ther objects of' the invention. will in part `be v'obviousand will in part appear hereinafter. The invention accordingly is directed to articles of manufacture the features, properties and relationship of elements of which will' be exemplied in the articles hereinafter described and the scope of the application of which will be indicated in the claims. f

' For a fuller understanding of the nature and Eobjects of the invention reference should be had tothe following detailed description taken in conjunction with the accompanying drawings in lwhich K Figure I is a longitudinal sectional view of an electrical swivel connection embodying the invention;

Fig. 2 is a similar view of an electrical appliance handle containing a modified form of swivel` i" connection embodying the invention; v

lFi'g.' 3 is a detail View of the lock Vring 'cflll'g 2; A 'i i Figs.4, 5, 6 and 'ifshow'successive steps in the ":a'ssernbly of the? swivel connection.lotl Fig. 2;!

een

iterior moutingj grnember.l

Fig. 8 is a` large scale showing of another modiecl form of electrical swive1 connection embodying the invention;

Fig. 9 is a sectional view along the line 9--9 thereof;

Fig. 10 is a view similar tolFig. 2 showing another modication; and

Fig. 11 showsy a step in the. assembly of the device of Fig. 10.

In the form of construction exempliiied in Fig. 1 there are provided a bearing 5 comprising balls 6 or other suitable rotary members held between an outer race 'I and an inner race 8, and a bearing IIJ comprising balls Il' or other rotary members held between an outer race I2 and an inner racev I3. The bearings are mounted only at their exteriors, the mounting vmeans being connected only to the outer races 'l and I2 and serving to electrically separate the bearings as well as to mount the same; Assembly is thus facilitated, and standard unit bearings may be used. In the present instance the mountingl is in the form of a sleeve I5 composed of insulating material such as phenol-formaldehyde kor methyl-methacrylate resins, for example, and of such diameter that Athe cuterl races 1' and? I l. can be frictionally fitted vfurtherestfrom the; body of' thev cord 20, this making for ease of assemblyl since the lead I8 may be soldered to` the left-hand side of the inner racev I3 before the bearing 5 is put in place and lead I9 soldered tothe left-hand side of the inner race 8 after the bearing 5 has been putin place.' However,'the leads may be soldered or otherwise permanently secured to any desired part or partsofthe inner races which may be found to be pratcical andconvenient in a particular instance, andas-wil1' be apparent, if they are secured to the nearyside rather than the far side of the inner races, the opening I6 in thefar bearing, e. g. the bearing 5, may be omitted. In any case, however, a veryy simple and readily assembled' device results vfrom extending the insulated connector through an openingl or'openings in theinner race or races rather `than thru an 'Desirablyfand as---exemplied there are pro- 3. vided means which will serve to prevent the bearings from contacting one another regardless of the conditions to which the swivel connection is subjected. To this end there is provided in the present instance an annulus 2| composed of insulating material and disposed between the bearing and the bearing I0; this annulus being desirably put in place after a lead has been connected with the inner race I3 but before the bearing 5 is put in place.

Desirably also there are provided dust caps 2Ia and 22-the latter being formed with a central opening 22d-which are frictionally tted within the sleeve I5. In assembly the dust cap 22 may be tted over the cord 20 as arst step in the assembly and the dust cap 2Ia slid into place after the lead I9 has beensecured to the inner race 8.

To the outer races 1 and I2 respectively there are soldered or otherwisepermanently secured insulated leads 23 and 24 which' may for example run to the terminals of an' electrical appliance, the ends of the leads being exposed for contact with 'their respective races. In the present instance the sleeve is cut away at 25 to permit the lead 23 to be soldered to the outside of the outer race 1 and is cut away at 26 to permit the lead 24 to be soldered to the outside of the outer race I2.

In the form of construction exemplified in Fig. 2, there are providedbearings 5b and Ich which are generally similar to the bearings 5 and I0. These are mounted in a sleeve I5b which in the present instance is molded with an integral inner annular projection 3D providing shoulders 3I and 32 against which the outer races 1b and I2b are adapted'to be disposed and which serve to positively prevent the bearings from moving toward each other. In the present instance, the leads I8b and I9b are soldered to' the far sides of the inner races 8b and I 3b respectively. Also in the present instance, the sleeve I5b is formed with a longitudinal groove 34 tor the reception of the lead 24h which exappliance to provide a portion` 36 which limits4 the movement of the swivel connection in one direction. In order to limit the movement of the swivelconnection in the other direction` the handle 35 is formed with an annular groove 31 just beyond the location of the swivel connection, and a lock ring 38 is adapted to be sprung into'this groove to hold the swivel connection in place. Desrably a removable dust cap 3S is inserted into the end of the handle after the lock ring'has been put in place, this being held in place by'one or more screws 40 so as'to be removable in ca se it is desired to remove the lock ringand the swivel connection. Pursuant to the invention in certain of its more specific aspects, the lock ring is specially formed'to facilitate its "easy removal. beinginteriorly distorted to pro- `vide a bend 4I which is readily engageable by a hook when removal is desired.

As shown in' Figs. 4 7, the swivel connection may bereadily assembled in" accordance with the invention bv slipping bearing' Illb over the leads lil'band 'ISb and soldering the'bare end `of the lead' I9b-tothe inner race I3b while the insu.- lated lead I 8b extends 'entirely through the opening I6 in the bearing Illlzv (Figli). .The

sleeve I5b is now slid into place, as shown in Fig. 6, whereupon the bearing 5b is put in place and the bare end of the lead I8b soldered to the inner race 8 thereof to provide the swivel connection of Figs. 2 and '1. The lead 24h is then laid in the groove 34 and the bare end thereof soldered to the outer race I2b; and the bare end of the lead 23 soldered to the outer race 1b.

As above indicated, the leads may be electrically connected with and permanently secured to the races in a wide variety of manners. In Figs. 8 9, there is exempliiied a form of construction wherein the connection is eiectuated by spot welding to the ends of the races. As exemplified, the lead I8c is soldered at 45 to a lug 46 which has been welded to the race 8c, the lead I9c is soldered at 41 to a lug 4B which has been welded to the race I3c, the lead 23o is soldered at 49 to a lug 50 which has been welded to the race 1c and the lead 24o is soldered at 5I to a lug 52 which has been welded to the race I2C. Each of the lugs 46, 48, 50 and 52 is formed in the present instance with a transversely extending tab 53 and the welding of lugs to their respective races is eectuated in the present instance by a spot weld 54. f

Instead of forming the sleeve as a unit and pressing the races into a sleeve, the sleeve may be so formed that it may be put on after the leads have been secured to the races. In the construction of Figs. 8-9 as exemplified, or the constructions of Fig. l or Fig. 2 or in other possible embodiments if desired, the mounting may be formed of a plurality of parts which are capable of ready assembly. In Figs. 8-l0. the insulating sleeve |50, which as exemplified is formed with an inner annular projection 30o similar to the projection 30, is axially divided so as to form in the present instance two identical semi-cylindrical parts 51 and 58 one edge of each of which is formed with protuberances 59 adapted to fit into holes 60 in a juxtaposed edge of the other. A slip ring 6I tting into two meeting semi-circular grooves 62 and 63 on the posts 51 and 58 respectively holds the sleeve in assembled position.

As will be seen, the member 58 is formed with a groove 34c for the reception of the lead 24e and is recessed at 64 for the reception of the lug 52. The member 60 is recessed at 65 for the reception of the lug 5D.

In certain instances, an appliance handle itself may constitute the mounting for the bearings. There is exemplified in Figs.. 10-11 .one such form of construction. Bearings 5d and I'Ild separated by an insulating washer 1D. are mounted directly in the handle 35d. A slin ring 38d tting into a shallow annular groove 31 holds the bearing assembly against a shoulder 36d.

Instead of running an insulated iiexible wir through the assembly to the far inner race. a stiff wire or elongated lug may be used. Figs. -10-11 also exemplify a construction of this sort. A stiff wire 1I is provided t0 connect the inner race i3d with the wire |911 and' a stiff wireV 4'I2 is provded to connect the inner race 8d with the wire I8d. The bent over ends 13 and 14 of Zthe stiff wires 1I and 'I2 respectively are spot welded "at 15 'and16 to the far ends of the races, this operation being preferably performed at a stage well in advance of, and if desired at a place-remote from, the stage and place of assembly.

iThus, each bearing-and-stiif-'wireV combination,

suchasI shown at the left-hand.endend. at lthe right-hand end of Fig. 11 can be as a unit.

Indeed, in various instances, as in certain electric appliances, one bearing willsuice for the swivel connection, the single bearing being mounted in an insulating handle, y'for example.

handled orl sold It is ordinarily desirable to insulate the wire ,V and to this end the invention contemplates the C use of a piece of tubular insulationv formed from plastic for example, as exemplified at 11.

Wires may be secured to the outer races as in the previously described forms. In the present exempliflcation, however, stiff wires 18 and 19 are likewise provided at these points, the bent over ends 80 and 8| thereof being spot welded at 82 and 83 respectively. In the present instance also the wire 'I9 on the left-,hand race is provided with an insulating tube 84 similar to the tube 11. longitudinal groove 85 of medium depth for the The handle 35d is for-med with a reception of the wire 18 and with alongitudinal 1 The fleXible Wires 18d, I9d, 23d, and 24d, may y.

be connected with their respective stiff wires in any suitable manner, as by soldering, preferably in a crimped sleeve as at 90; the soldering operation of the wires I8d and I9d being preferably performed before the insertion of the bearing 5d or the bearing assembly, if the assembly is first formed, into the handle, and the crimped portion taped.

The several electrical connections exemplified above are adapted for use with a wide variety of electric appliances such for instance as electric irons, electric soldering irons, electric hair curlers, etc., and also as connections for such devices as electric lights, electric plugs, and the like.

Since certain changes may be made in the constructions set forth and in carrying out the above method, and different embodiments of the invention may be provided Without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying-drawing shall be interpreted as illustrative and not iria limiting sense. i

What is claimed is:

1. In combination an electrical swivel connecy tion comprising a plurality;t of spaced bearing? each having an outer conductive race disposef' further from the axis thereof and an inner con ductive race nearer to the axis thereof and ro tatable conductive members therebetween anj providing a conductive path therethru, each o said bearings extending about said rotatabl members in one direction along said axis anL in the other direction along said axis to grip th same on both sides whereby each race will itself prevent movement of the rotatable members the direction of the axis, an exterior mounting for said bearings, said mounting providing insuilf lation for electrically separating said bearing,A the inner race near at least one end of the con-'fi' nection having a central opening therethru which is unobstructed andsaid connection being" so formed that said opening continues unobstructed to another of said inner races, and a pair of electrical conductors extending thru said-r opening and respectively connected directly tof the last-mentioned races whereby free relative' rotation between the outer races and said con-j;

ductors will occur, a casing adapted to receive',

said connection and provided with means for limiting its movement in one direction, and re` y leasable means for limiting the movement of said.r connection in the other direction.

2. An electrical swivel connection as set forth in claim l wherein the conductors are spot-welded to the respective inner races.

3. An electrical swivel connection as set forth in claim 1 wherein the releasable means is in the form of a split ring.

THOMAS H. FAILE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 

